Optical Redox Imaging of Fixed Unstained Muscle Slides Reveals Useful Biological Information.
Optical Redox Imaging of Fixed Unstained Muscle Slides Reveals Useful Biological Information.
复制标题
固定未染色肌肉切片的光学氧化还原成像揭示了有用的生物学信息。
DOI：
10.1007/s11307-019-01348-z
复制
发表时间：
2019
影响因子：
3.1
通讯作者：
Li,LinZ
中科院分区：
文献类型：
--
作者：
Xu,HeN;Zhao,Huaqing;Chellappa,Karthikeyani;Davis,JamesG;Nioka,Shoko;Baur,JosephA;Li,LinZ
PurposeOptical redox imaging (ORI) technique images cellular autofluorescence of nicotinamide adenine dinucleotide (NADH) and oxidized flavoproteins (Fp containing FAD,i.e., flavin adenine dinucleotide). ORI has found wide applications in the study of cellular energetics and metabolism and may potentially assist in disease diagnosis and prognosis. Fixed tissues have been reported to exhibit autofluorescence with similar spectral characteristics to those of NADH and Fp. However, few studies report on quantitative ORI of formalin-fixed paraffin-embedded (FFPE) unstained tissue slides for disease biomarkers. We investigate whether ORI of FFPE unstained skeletal muscle slides may provide relevant quantitative biological information.ProceduresLiving mouse muscle fibers and frozen and FFPE mouse muscle slides were subjected to ORI. Living mouse muscle fibers were imagedex vivobefore and after paraformaldehyde fixation. FFPE muscle slides of three mouse groups (young, mid-age, and muscle-specific overexpression of nicotinamide phosphoribosyltransferase (Nampt) transgenic mid-age) were imaged and compared to detect age-related redox differences.ResultsWe observed that living muscle fiber and frozen and FFPE slides all had strong autofluorescence signals in the NADH and Fp channels. Paraformaldehyde fixation resulted in a significant increase in the redox ratio Fp/(NADH + Fp) of muscle fibers. Quantitative image analysis on FFPE unstained slides showed that mid-age gastrocnemius muscles had stronger NADH and Fp signals than young muscles. Gastrocnemius muscles from mid-age Nampt mice had lower NADH compared to age-matched controls, but had higher Fp than young controls. Soleus muscles had the same trend of change and appeared to be more oxidative than gastrocnemius muscles. Differential NADH and Fp signals were found between gastrocnemius and soleus muscles within both mid-aged control and Nampt groups.ConclusionAging effect on redox status quantified by ORI of FFPE unstained muscle slides was reported for the first time. Quantitative information from ORI of FFPE unstained slides may be useful for biomedical applications.
